Not sure what to think.

Hey girls, so I recently started dating this guy about 4 months ago. Overall he is great, very kind loving funny, he is great with my son which I love. But I’m having a problem. We have had sex multiple times, every time it’s great we both enjoy it to the fullest and he never fails to tell me how badly he wants to do it again and how much he loves having sex with me etc in the act he he seems to love it, we tend to go on for hours at times BUT he NEVER cums . We have had sex at least 10 times easily ..... and he NEVER cums. He definitely makes sure that I do but it just never happens for him. Idk what to think. If it’s me ( tho he never makes me feel unwanted ... more like the opposite ) or if he has a problem and is afraid to tell me. I feel bad asking him because I don’t want to hurt his feeling or for him to feel embarrassed but I obviously know that’s what I should do and I will. Just curious to know what you guys think.